1. Technical Field
The inventive concept relates to a method of fabricating a semiconductor device. More particularly, the inventive concept relates to a method of fabricating a thin film of a semiconductor device in an opening having a high aspect ratio.
2. Description of the Related Art
As semiconductor devices become more highly integrated and miniaturized, techniques for increasing the capacitance of dynamic random access memory (DRAM) devices are increasingly needed. To increase the capacitance in a limited area, various methods may be used such as using a high-k dielectric material as a dielectric layer, reducing the thickness of a dielectric layer, and increasing the effective area of a lower electrode.
To increase the effective area of a lower electrode, the lower electrode may be integrally formed, and the height of the lower electrode may be increased. That is, a cylindrical, stack-type, or concave-type lower electrode may be formed. In these cases, the lower electrode may have significant size in all three dimensions and an interior having a relatively high aspect ratio (ratio of height to width). However, there is a difficulty in forming a thin film having a uniform thickness on a three-dimensional (3D) lower electrode whose interior has a high aspect ratio.